This invention relates to side hammer percussion locks and particularly to a safety for such devices.
Percussion firearms remain popular with collectors, with both originals and reproductions available. While the side hammer percussion lock was never widely utilized, with the present invention it can be made to have a degree of safety which was heretofore not available with percussion firearms. In any percussion firearm a certain degree of danger exists whenever it is capped. In order to cap the nipple the hammer must either be placed in its cocked position, or in a half cocked position if such is available, or else the hammer must be pulled away from the nipple while the cap is being installed. If the firearm is placed in its fully cocked position is is susceptible to accidental discharge either by inadvertent pulling of the trigger or by the hammer accidently being dislodged. While a half cocked position decreases this danger, there is still a possibility that the cap will explode if the hammer is released, and if the hammer is forcibly released, such as by dropping the firearm, inadvertent firing becomes quite likely. Even when the cap is installed by pulling the hammer slightly away from the nipple and then resting it back on the cap, it is possible to inadvertently discharge the firearm by dropping it in a way in which the hammer is forced into the cap or by bumping the hammer in a manner to cause the same results.
What is needed therefore is a safety position for the hammer of a percussion firearm, where the nipple is exposed for capping and the hammer cannot thereafter strike or be forced against the cap until the safety is released.
The present invention overcomes the foregoing limitations and shortcomings of prior art percussion locks by providing means for displacing the hammer from its normal position to a safety position where it cannot be brought into contact with the percussion cap.
In a first embodiment of the invention the hammer fits within an opening in the lock plate which mounts the hammer assembly to the firearm. A slot located in the hammer co-planar with the opening allows the hammer to be slidably transmitted between its normal and safety positions. A hammer latch, which is rotatably mounted on the hammer is normally biased to a locking position by means of a spring. When the hammer is in its normal position a tang on the hammer latch co-acts with a bearing surface, defined by the rear of the opening in the lock plate, to provide the pivot point about which the hammer rotates between its cocked and firing positions. To translate the hammer to its safety position, the hammer latch is released, so that the tang is removed from the bearing surface, and the hammer is slid rearwardly until the front of the slot in the hammer co-acts with the bearing surface. When the hammer is in its safety position the hammer latch tang fits into a lock-engaging cavity in the lock plate and thus locks the hammer in this position.
In a similar embodiment the hammer does not rotate about the bearing surface at the rear of the opening in the lock plate but instead rotates about a pin which extends between flanges that extend outwardly from the lock plate. Thus the pivot point is spaced further outwardly from the point at which the hammer is attached to the main spring which pulls it to its firing position, thereby increasing the striking force of the hammer.
In a third embodiment of the invention the hammer is not displaced to its safety position by being translated but instead is rotated about an axis which is perpendicular to the axis about which the hammer moves between its cocked and firing positions.
In this embodiment the hammer is divided into an inner portion which is pivotally joined to the lock plate in a manner to allow the hammer to move between its cocked and firing positions, and an outer portion which is pivotally mounted to the inner portion. Thus the hammer is moved between its normal and safety positions by rotating the outer portion relative to the inner portion. In this embodiment rather than providing a lock, detents are provided between the two portions of the hammer to prevent inadvertent movement of the outer portion of the hammer between its safety and normal positions.
In all but one embodiment a cam located on the lock plate interacts with the hammer to lift it off of the percussion cap when the hammer is moved to its safety position in order to prevent inadvertent explosion of the cap due to its being hit by the hammer when the hammer is returned to the normal position.
Accordingly, it is a principal objective of the present invention to provide a safety for a side hammer percussion lock wherein the hammer is displaced from the percussion cap when it is in the safety position.
It is a further object of the present invention to provide such a device wherein the hammer cannot be brought into contact with the percussion cap while it is in its safety position.
It is a still further object of the present invention to provide such a device which includes means to prevent inadvertent movement of the trigger between its safety and normal positions.
It is a further object of the present invention to provide such a device where the hammer is lifted off of the percussion cap when it is moved from its normal firing position.